386 
VEGETABLE GARDENING 
or 8 inches, the usual plan, and ( 2 ) by driving stakes 
at the ends of the rows and at frequent intervals and 
then stretching cheap twine on either side. When ma- 
ture or ripe the heads turn yellow. At this stage they 
should be removed promptly with 6 to 8 inches of the 
stalk before any seed is lost. As the tops do not ripen 
at the same time, it is necessary to make several cuttings 
to prevent loss. A tight vessel, or basket with a cloth 
lining, should be used in collecting the seed. The tops 
are spread in an airy room with a tight floor until dry 
enough to separate with a flail or by other means. Win- 
nowing will remove most of the chaff. The seeds may 
then be placed, a few pounds at a time, in a vessel of 
water. The heavy seeds, which sink, are saved, while the 
light ones and the remaining chaff are poured off. After 
thorough drying and curing, the seeds may be stored 
in any dry room. 
533. Soil preparation. — The method of soil preparation 
will depend mainly upon the character of the soil, and 
the crops previously grown. Fall plowing is often an 
advantage, especially for pastures, heavy sods, muck 
lands and clay loams. A favorite practice before plant- 
ing any field in onions for the first time is to grow the 
previous year a crop, such as potatoes or corn, which 
requires thorough cultivation. Coarse stable manures 
may also be used the year before planting onions. Such 
a course of treatment will rid the land of troublesome 
weeds and increase the supply of humus. Rotation is 
highly desirable, as it Is a means of reducing loss from 
fungous diseases and insect pests and of maintaining 
proper soil conditions. Other vegetables, as spinach, 
celery, beans, lettuce, etc., may be used with profit. The 
selection of the other crops in the rotation must be de- 
termined by market, soil, moisture, climate and labor 
conditions. 
Whatever crops are grown previous to planting on- 
